add exitcode
diff --git a/src/lib9/mkfile b/src/lib9/mkfile
index 556be2f..a244dd3 100644
--- a/src/lib9/mkfile
+++ b/src/lib9/mkfile
@@ -99,6 +99,7 @@
 	errstr.$O\
 	exec.$O\
 	execl.$O\
+	exitcode.$O\
 	fcallfmt.$O\
 	get9root.$O\
 	getcallerpc-$OBJTYPE.$O\